Questions about Mathematica's date and time functions.

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3
votes
2answers
53 views

Using Dataset with TimeObjects in EventSeries

I'm new to Mathematica, and while this is potentially quite easy, I'm having difficulty using TimeObjects in the EventSeries ...
0
votes
2answers
38 views

TimeSeriesAggregate—reformatting the date

Compute Aggregated Statistics for a Time Series The article linked to above provides a sample of aggregating time series data. ...
0
votes
2answers
33 views

Read timeseries data from CSV

I am new to Mathematica and have v10. I would like to you use the new TimeSeriesAggregate[tsdata, "Quarter", Total] feature to return aggregated descriptive stats. I import a number of columns of ...
2
votes
1answer
49 views

How to set proper time zone for weather data

I am running a query to pull historical temperature readings from Los Angeles using the following query: ...
4
votes
2answers
90 views

Set hour of DateObject

Say I have a date object date = DateObject[{2016, 7, 17, 0, 0}], how do I later change the hour of that date object, without needing to know the value it currently ...
-4
votes
0answers
44 views

How to add new formula in existing formula in certain time?

Good day, May anyone help me to give an idea to edit the coding For as below towards my problems. ...
4
votes
0answers
132 views

Predicting Manhattanhenge

At the time of writing, Manhattanhenge is tonight in New York City (ref 1), "an event during which the setting sun is aligned with the east–west streets of the main street grid of Manhattan, New York ...
-2
votes
0answers
54 views
1
vote
1answer
47 views

How to convert output time in terms of seconds to minute with UnitConvert[]? [duplicate]

I have this code: AbsoluteTiming[g[x_, t_] := Sin[x]^90*(1 + t^2); Integrate[g[x, \[Tau]], {\[Tau], 0, t}]] with this output: I want to have convert unit to ...
0
votes
0answers
31 views

Using DatePlus with a list of dates and list of times to add

I have a list of dates such as t2 = {"2016-06-08 05:00:00", "2016-06-08 05:00:00", "2016-06-08 05:00:01"} and a list of offsets (in seconds), such as ...
5
votes
1answer
70 views

How to specify RegularlySampledQ TimeSeries with EndOfMonth date unit MinimumTimeIncrement?

"EndOfMonth" is date unit that can be used with date functions. When specifying a TimeSeries object with date increments you ...
0
votes
1answer
35 views

Select Time Phase of Dataset with SQLDateTime Objects

I have a Dataset like this: ...
5
votes
1answer
55 views

How to prevent TimeSeries adding TimeObject parameter and TimeZone option to DateObjects?

TimeSeries adds a TimeObject parameter and a TimeZone option to ...
4
votes
1answer
63 views

DateObject with DateFormat displays incorrectly in Dataset

DateObjects with DateFormat option appear to have the first date part truncated when displayed in a ...
6
votes
2answers
101 views

Speed up AbsoluteTime with string input

I have millions of strings representing dates in the form: "05-Mar-2004 10:15:00". I would like to convert these to absolute times. For example: ...
7
votes
4answers
229 views

Getting AbsoluteTiming to display in hours, minutes, and seconds

I'm doing some extended length calculations and was wondering how I could get AbsoluteTiming to display in hours, minutes, and seconds. I googled and found nothing, ...
4
votes
4answers
432 views

How to convert Dates with format 2016/03/1 to become {2016,3,1}

I have a problem to convert tide data with the form as follows. 2016/03/23,08:00,0.89,* 2016/03/23,09:00,1.41,* 2016/03/23,10:00,1.67,* 2016/03/23,11:00,1.44,* 2016/03/23,12:00,0.82,* 2016/03/23,13:...
3
votes
1answer
63 views

overlap of data

I have two individual Date lists as Date Objects: List 1 = {1 Jan 1991 9 :00 , 3 Jan 1991 11:00 ..etc } List 2 ={ 7 Jan 1991 14:00, 9 Jan 1991 15:00 ..etc} For ...
4
votes
2answers
88 views

How to override DisplayForm of (mixed) time Quantity

What's the best approach to overriding DisplayForm for specific types of Quantity eg time especially w/ mixed units? Current is ...
3
votes
1answer
92 views

How to plot the hour of the sunsets

i have this code: ...
-1
votes
2answers
65 views

Matching timestamped data

I bet this question is a gimme for most of you guys, but I'm having a bit o' trouble figuring it out. Thanks ahead of time for your input and help. Soooo, I have two datasets where column 1 is a ...
8
votes
2answers
230 views

How to skip weekends in DateListPlot?

How to skip weekends in DateListPlot, ie, drawing 20 something data points for a month and not leaving 2 days gap between weeks? Currently DateListPlot occupied the actual number of days for a month ...
0
votes
1answer
59 views

Combining first 5 columns from CSV file into AbsoluteTime date

Thanks in advance for all your help. I need to import data from a CSV file that looks like : (easier to read in excel) I would like to convert the data into timestamps by creating a Table with 2 ...
3
votes
1answer
50 views

How to get DateListPlot Epilog to display shapes

The following should produced a plot with an orange outlined disc labelled "A" on the dotted line. Epilog produces the dotted line and the text label but is unable ...
2
votes
1answer
109 views

Automatic text-wrapping in labels in `TimelinePlot`

Part-related to this question and part-related to this one, I would like to make use of the new features of TimelinePlot in 10.3, but would like to incorporate some ...
3
votes
0answers
51 views

Possible Bug with DateObject

So my questions is going to be hard to duplicate because I am not sure when or why it happens. I've read here several bugs with DateObject, but none of them ...
5
votes
1answer
54 views

How to modify wrong time zone in a Date object?

How can one modify the wrong time zone in a DateObject, without a conversion? Can one manipulate the TimeZone directly without having the numerical value of the time changing?
0
votes
0answers
44 views
2
votes
1answer
101 views

working hours and negative time [closed]

I have a list of TimeObjects. I want to subtract 5h from each element and if TimeObject < 5h then give a negative hour. My ...
4
votes
1answer
55 views

TimelinePlot - Handling dates prior to Year Zero

Interested in Using TimelinePlot to help me understand/remember important time periods in Earth prehistory and history. Following an a simple example in the Documentation I create a TimelinePlot for ...
5
votes
2answers
101 views

How can DateObject handle calender weeks

I have dates given for a TimeLinePlot. These dates are in {year,week} format. DateObject ...
6
votes
2answers
156 views

Plot time along the y-axis?

How can I plot times along the Y-axis, (with dates along the X-axis) e.g. ...
2
votes
2answers
44 views

Date Conversion Using Regular Expressions on “Incomplete” Date Formats

I have a list of dates in one of the following formats: "1999/05/12", "1999/05/", "1999//", "****//**/", "" so that a list of such dates might appear as ...
1
vote
1answer
93 views

Why do I get different results for the same input specified using natural language phrasing? [closed]

One of the comments to Stephen Wolfram's blog post on Ada Lovelace, mentioned that WolframAlpha (and verified in Mathematica as well) provided slightly different results for the question of Ada's age ...
1
vote
0answers
34 views

Save a Mathematica notebook evaluated [duplicate]

My notebooks can take some time to evaluate and by quitting Mathematica, I have to reevaluate every definition I've made once I restart Mathematica. Is there a way to tell Mathematica to save the ...
4
votes
2answers
164 views

Finding the positions DateList dates in a range in large data set

There are similar questions to this like list search but this question is focused on finding at subset of dates in DateList format within a range of specified dates ...
5
votes
2answers
167 views

How to convert date string with fractional seconds to DateObject

I have a date/time string from a data file in the form "2014/01/09 07:24:36:001". I would like to convert it to a DateObject. I ...
10
votes
1answer
184 views

DateDifference isn't consistent when giving result in years

This isn't really causing me a problem at the moment, but it's weird. Is this documented anywhere? When I ask for the difference in days and then in years between April 1, 2015 and October 1, 2015 ...
4
votes
1answer
81 views

Working with dates & times - nonatomic expression expected [closed]

Please note that I am new to Mathematica. I am endeavouring to import data from a CSV file with the first column a date and time. The import appears to work fine and returns the results I expect: <...
5
votes
3answers
98 views

How to ignore year in DateListPlot

I just upgraded to Mathematica 10, and I am trying to get the hang of the new TimeSeries data objects, which are preventing my old strategy of overlaying data from ...
4
votes
0answers
38 views

DateObject's DateFormat option has inconsistent result in TimelinePlot LabelingFunction and by direct call

I want to strip time and time zone from dates in the LabelingFunction of a TimelinePlot. I am using the ...
7
votes
1answer
617 views

Why does Mathematica's date for the battle Agincourt differ from the US Navy's?

If I ask Mathematica for the Julian Date for the battle of Agincourt with WolframAlpha["battle of agincourt date"] it reports ...
2
votes
1answer
115 views

DateListPlot show iso week

How can I make DateListPlot show the iso week number? I would like to make a Date plot so that for each dot it will show the iso week date in the x-axis .
13
votes
4answers
370 views

How to evaluate the second argument of Cases only once

I'd like to find a fast but readable way to achieve the following: ...
1
vote
1answer
42 views

Aborting an evaluation automatically after a specified time elapsed

I use the following code to evaluate a series of notebooks: nb1 = NotebookOpen["C:\\Users\\....nb"]; SelectionMove[nb1, All, Notebook] SelectionEvaluate[nb1] ...
3
votes
2answers
123 views

Troubles importing date and time from CSV file

I'm trying to import CSV file with the following format: 20150803 00:00:01.649,1.09675,1.09678 using this code: ...
3
votes
2answers
171 views

Convert DateObject into TimeObject

How to elegantly convert from DateObject to TimeObject? The purpose is to extract time from the DateObject and manipulate only ...
7
votes
1answer
166 views

Determining FinancialData for Countries

How do I determine the FinancialData for Australia. For instance the one for USA follows as: FinancialData["NYSE", "Members"] ...
5
votes
1answer
108 views

DatePlus changes in V10.2, can I return to previous behaviour?

Now in V10.2, DatePlus has changed it behaviour in a undocumented way. Now, DatePlus[n] (with n as ...
2
votes
1answer
109 views

DateListPlot incorrect time zone [closed]

I'm trying to plot energy usage over time using datelistplot but the time zone on the ticks is wrong, data for 7pm shows as 3am The code: ...